TY - JOUR
T1 - Survey of ring current composition during magnetic storms
AU - Grande, M.
AU - Perry, C. H.
AU - Hall, Adrian M.
AU - Fennell, J.
AU - Wilken, B.
N1 - Funding Information:
M. Grande and C. H. Perry were supportedin part by grant AFOSR-X5-0237 from the US Air Force to RutherfordA ppleton Laboratory. The work of J. F. Fennellw ass upportebdy theU S.Air Forceu nderc ontract F04701-9lC-00X9.A Hall wasj ointly supportedun dera CASE studentshibpy PPARC andC CLRC.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 1997
Y1 - 1997
N2 - During geomagnetic storms, the ring current is substantially modified and intensified. We use data from the MICS instrument on CRRES to investigate composition changes in magnetospheric ions in the energy range 20-400 keV/e. These are related to the Dst signature of the storm. Long term survey plots of MICS data show that during storms there is an initial increase of ionospheric material at around L=3. The peak in the ratio of ionospheric material rises to higher L-shells during the storm recovery. By contrast, solar wind material remains predominantly at higher L-shells, and a belt of ring current alpha particles forms around L=4. The L-shell of the peak fraction of ionospheric material is a strong function of Dst. Substorm composition reflects the background composition at that L-shell. These results are emphasised by a superposed epoch analysis of substorm injection composition. It shows that the composition of storm time injections is similar to a set of oxygen rich injections. We conclude that, during the solar maximum interval which CRRES observed, substorms are not directly responsible for the ring current oxygen population.
AB - During geomagnetic storms, the ring current is substantially modified and intensified. We use data from the MICS instrument on CRRES to investigate composition changes in magnetospheric ions in the energy range 20-400 keV/e. These are related to the Dst signature of the storm. Long term survey plots of MICS data show that during storms there is an initial increase of ionospheric material at around L=3. The peak in the ratio of ionospheric material rises to higher L-shells during the storm recovery. By contrast, solar wind material remains predominantly at higher L-shells, and a belt of ring current alpha particles forms around L=4. The L-shell of the peak fraction of ionospheric material is a strong function of Dst. Substorm composition reflects the background composition at that L-shell. These results are emphasised by a superposed epoch analysis of substorm injection composition. It shows that the composition of storm time injections is similar to a set of oxygen rich injections. We conclude that, during the solar maximum interval which CRRES observed, substorms are not directly responsible for the ring current oxygen population.
UR - http://www.scopus.com/inward/record.url?scp=0009686423&partnerID=8YFLogxK
U2 - 10.1016/S0273-1177(97)00675-3
DO - 10.1016/S0273-1177(97)00675-3
M3 - Article
AN - SCOPUS:0009686423
SN - 0273-1177
VL - 20
SP - 321
EP - 326
JO - Advances in Space Research
JF - Advances in Space Research
IS - 3
ER -